Synonyms of overnight

Adjective

1. nightlong, all-night, overnight, long (vs. short)

usage: lasting, open, or operating through the whole night; "a nightlong vigil"; "an all-night drugstore"; "an overnight trip"

Adverb

1. overnight

usage: during or for the length of one night; "the fish marinates overnight"

2. overnight

usage: happening in a short time or with great speed; "these solutions cannot be found overnight!"

Definition and meaning of overnight (Dictionary)